Cranial Reconstruction Using Autologous Bone and Methylmethacrilate.

BACKGROUND: Having in mind the importance of reconstruction of the calvaria, our goal was to compare the complication rates following the use of autologous bone and methylmethacrilate grafts, and explain the factors influencing them. METHODS: The authors collected information of all the patients undergoing cranial reconstructive surgery (N = 149) at the Military Medical Academy in Belgrade. Procedures were performed either using a craniotomy bone flap, removed and replaced in the same act, or using methylmethacrilate. These 2 groups were compared using the Chi-squared test, controlling for the confounding influence of the size of the defect. RESULTS: Intracranial neoplasms were the cause for the reconstruction in 71.1% of patients. The total complication rate was 7.4%, while the infection rate was 5.4%. The infection rate was significantly higher in those procedures done using methylmethacrilate (11.3% compared with 2.1%, P = 0.017), but when controlling for the confounding effect of the size of the defect treated, the difference in infection rate was significant only in large defects (13.9% compared with 2%, P = 0.031), while for small defects the difference was not statistically significant. CONCLUSIONS: Our study suggests that the material used for reconstruction of calvaria influences the infection rate only in large and complicated defects. Considering the importance of the reconstruction, further studies should explore and confirm the role of material type on the rate of complications.

Intrusion Characteristics of Three Bone Cements for Tibial Component of Total Knee Arthroplasty in a Cadaveric Bone Model.

The purpose of this study was to evaluate and compare the intrusion characteristics of Simplex-HV to Simplex-P and Palacos-R in cadaveric proximal tibial bone. Eighteen fresh-frozen cadaver proximal tibiae were examined with standard arthroplasty tibial cuts. Each tibia was randomly assigned to receive one of the three bone cements for use with finger packing technique. Sagittal sections were prepared and analyzed using digital photography and stereoscopic micrographs to evaluate cement intrusion characteristics. The cement penetration depth was measured from the tibial bone cut surface, which did not include the cement thickness under the tibial base plate. Significant differences were detected in the bone cement penetration between the three cements. Penetration was increased using the Simplex-HV (average, 2.7 mm; range, 2.0-3.0 mm) compared with Simplex-P (average, 2.2 mm) and Palacos-R (average, 1.8 mm). These depths approximate to 3.7, 3.2, and 2.8 mm of total cement penetration, respectively. The data suggest that high-viscosity bone cement may provide good fixation of the tibial component of a total knee arthroplasty when using the finger packing technique.

Aesthetic occiput augmentation using methylmethacrylate.

Cranioplasty for only aesthetic reasons has not been commonly performed to date. However, recently there has been a new focus by the public on a more aesthetically pleasing head shape with frequent patient requests for purely aesthetic contouring of the occiput, an important definer of cosmetic head shape. For example, in Asia, where the normal cranial shape is mesocephalic or brachycephalic and often with a planar occiput, requests for its aesthetic correction are increasingly common. Accordingly, the author developed a minimally invasive occiput augmentation using methylmethacrylate. In this study, the indications for aesthetic occiput contouring were planar occiput, left-right asymmetric occiput, and grooved occiput. Under local anesthesia, soft methylmethacrylate is subperiosteally inserted through a small incision (about 5-cm length), manually and precisely contoured in situ through the scalp to the desired occipital shape. All is performed as an outpatient procedure, and a quick recovery is the case. Between March 2007 and October 2013, 959 patients received such aesthetic occiput augmentation. The mean follow-up period was 49 months (range, 3-84 months). Nearly all patients were satisfied with the outcome, and complications were very rare. Only 5 patients (0.5%) needed additional corrective procedures. The author has concluded that aesthetic occiput augmentation using methylmethacrylate yields consistent, predictable, and satisfactory results. Additional long-term follow-up is required for a final conclusion, however.

Microtensile bond strength of different acrylic teeth to high-impact denture base resins.

PURPOSE: This study evaluated the effect of denture base acrylic, denture tooth composition, and ridge-lap surface treatment on the microtensile bond strength (µTBS) of three commercially available denture teeth and two injection denture processing systems. MATERIALS AND METHODS: Sixteen experimental groups were formed (n = 3), according to denture tooth surface treatment (no treatment or surface treatment recommended by the manufacturer), denture base processing technique and acrylic (SR-Ivocap-Ivocap Plus or Success-Lucitone 199), and tooth type-composition at bonding interface (BlueLine DCL-PMMA, Portrait IPN-PMMA, Phonares II-PMMA, Phonares II-NHC). Rectangular bar specimens with a 1 mm(2) cross sectional area were fabricated and subsequently thermocycled at 10,000 cycles between 5°C and 55°C with a 15-second dwell time. Select specimens underwent µTBS testing in a universal testing machine with a 1 kN load cell at 0.5 mm/min crosshead speed. Data were analyzed statistically by two and three-way ANOVA and Tukey post hoc test (α = 0.05). RESULTS: Mean µTBS ranged between 56.2 ± 5.6 and 60.8 ± 5.0 N/mm(2) for the Ivocap Plus specimens and 13.3 ± 5.12 to 60.1 ± 6.0 N/mm(2) for the Lucitone 199 specimens. Among the Ivocap specimens, BlueLine DCL and Phonares II NHC had significantly higher µTBS than Portrait IPN to Ivocap Plus acrylic. There were no statistically significant differences among Blueline, Phonares II PMMA, and Phonares II NHC, or between Phonares II PMMA and Portrait IPN. Within the Luctione 199 specimens, there was a significantly higher µTBS for BlueLine DCL and Phonares II NHC denture teeth with the manufacturer-recommended surface treatment when compared to control surface. BlueLine, Portrait, and Phonares II PMMA groups achieved significantly higher mean µTBS than the Phonares II NHC group. There were no statistically significant differences among BlueLine, Portrait, and Phonares II PMMA groups. CONCLUSION: When evaluating the µTBS of PMMA and NHC denture teeth to base resins, a stronger bond was achieved using materials produced by the same manufacturer. Within the Luctione 199 specimens, the Phonares II NHC group demonstrated significantly lower bond strength than other specimens, suggesting that gross ridge-lap reduction of NHC denture teeth is not recommended if a base acrylic by a different manufacturer from the tooth is going to be used.

Bone marrow stimulation induces greater chondrogenesis in trochlear vs condylar cartilage defects in skeletally mature rabbits.

OBJECTIVE: The aim of this study was to compare the early repair response of cartilage defects in trochlea (TR) and medial femoral condyle (MFC) at 2-3 weeks after bone marrow stimulation. DESIGN: Bilateral full-thickness cartilage defects were generated in central trochlear groove and MFC of skeletally mature rabbits. Four subchondral perforations were made on each defect, either by microfracture to 2 mm deep, or by drilling to 2 mm or 6 mm deep. Rabbits were sacrificed either on Day 14 post-operatively or on Day 21. Defects were analyzed by histology, stereology, histomorphometry and micro-computed tomography (CT). Intact femurs (N = 4) served as controls. RESULTS: Stromal cell density recruitment was similar in all defects, irrespective of defect location and surgical techniques used. There was a robust appearance of chondrocytes at Day 21 in TR defects with significantly higher volume fraction of chondrocytes in TR compared to MFC (P = 0.013). Chondrogenic foci were observed in marrow penetrating holes, with a significantly higher frequency and larger foci in TR vs MFC defects at Day 21 (P = 0.043 and P = 0.0014, respectively). Micro-CT analysis showed that deep drilling elicited significantly more mineralized bone fill compared to shallower perforations at 2 and 3 weeks repair (all at P ≤ 0.0008). CONCLUSIONS: Bone marrow stimulation induced greater chondrogenesis in TR vs MFC defects in adult rabbits, with more chondrocytes and larger chondrogenic foci appearing in TR vs MFC on Day 21 post-operation.

Case reports: Treatment of traumatic triradiate cartilage epiphysiodesis: what is the role of bridge resection?

BACKGROUND: Acetabular fractures are rare in children and can be complicated by premature fusion of the triradiate cartilage resulting in secondary acetabular dysplasia. Early recognition and treatment of a physeal bar in this location can be difficult. The purpose of this case report was to investigate whether early intervention could restore acetabular growth and prevent secondary acetabular dysplasia as measured on plain radiographs. CASE DESCRIPTION: We report a series of three patients (3, 4, and 5 years old) who underwent physeal bridge resection and methylmethacrylate or fat interposition through an extended Pfannenstiel approach. The mean followup was 6 years. After resection of the osseous bridge the physis initially remained open with evident acetabular growth in all three patients. In one patient, the bridge reformed 6 years after the procedure. All patients had a slight increase in the thickness of the acetabular wall relative to the contralateral side but no radiographic evidence of acetabular dysplasia. LITERATURE REVIEW: To our knowledge, there are only two reports of physeal arrest resection of triradiate cartilage with one successful result. CLINICAL RELEVANCE: Posttraumatic, partial physeal arrest of the triradiate cartilage may be treated with resection of the bone bridge resection through an extended Pfannenstiel approach. The potential benefits of this treatment must be weighed against the risks.

Single centre prospective study of the efficacy of percutaneous cement augmentation in the treatment of vertebral compression fractures.

INTRODUCTION: Despite controversial outcomes of recent published trials, percutaneous cement augmentation remains widely used in managing painful vertebral compression fractures. We prospectively assessed patients with such fractures using an eleven-point visual analogue scale for pain and the Qualeffo 41 questionnaire for quality of life. METHODS: Consecutive patients undergoing percutaneous cement augmentation for painful vertebral compression fractures were recruited. Patients were assessed pre-procedure by completing a visual analogue scale for pain, on a scale of 0 to 10. A Qualeffo 41 questionnaire was also completed. Patients were followed up at 1 week and 3 months. RESULTS: Fifty six patients were prospectively recruited (111 vertebroplasty and 5 kyphoplasty). Visual analogue scores dropped from 6.4 ± 2.3 pre-procedure to 4.0 ± 2.7 at 1 week (p < 0.0001) and 4.3 ± 2.7 (p < 0.0001) at 3 months. Three subgroups were identified; osteoporotic patients (n = 28), a second non-osteoporotic group (n = 20) who had acute fracture following fall and a third group with compression fractures secondary to metastatic disease (n = 8). At 3-month follow-up, patients with osteoporotic fractures had reduction in pain score from 6.3 ± 2.1 to 4.8 ± 2.7 (p = 0.02). Patients who had traumatic fractures experienced more significant pain relief, 6.4 ± 2.6 to 3.8 ± 2.7 (p = 0.0009) but patients with malignant fracture had most benefit, 6.0 ± 3.0 to 1.8 ± 0.8 (p = 0.01). Total Qualeffo scores improved from 63 ± 15 to 49 ± 22 (p < 0.0001). Within the domains of the Qualeffo questionnaire, most improvement was seen in pain and physical function. Median in-patient stay post procedure was one day. CONCLUSION: In our experience percutaneous cement augmentation is safe and efficacious in the management of painful VCF related to osteoporosis, trauma and cancer, achieving rapid and significant pain reduction and improvement in physical function as measured with a visual analogue scale and the Qualeffo 41 questionnaire.

Management of cranial bone defects: a reconstructive algorithm according to defect size.

INTRODUCTION: Reconstruction of cranial bone defects is one of the most challenging problems in reconstructive surgery. The timing of reconstruction, the location of the defect, the materials to be used, and the medical history of the patient are parameters that have been mostly discussed in the literature. To the best of our knowledge, there has not been any published classification for the cranial bone defect reconstruction according to defect size. MATERIALS AND METHODS: Twelve patients underwent reconstruction of cranial vault defects. Cranial bone defects were classified into 3 groups according to the size of the defect. The small-sized group included the defects smaller than 25 cm(2), the medium-sized group included the defects between 25 to 200 cm(2), and the large-sized group included the defects larger than 200 cm(2). The small-sized defects were reconstructed with split calvarial graft, demineralized bone matrix, or hydroxyapatite cement; the medium-sized defects were reconstructed with split calvarial graft or allogenic bone graft; and the large-sized defects were reconstructed with methyl methacrylate, autoclaved bone, or porous polyethylene. RESULTS: Two patients needed revision for irregularities with demineralized bone matrix. Other patients had no skull defects or irregularities for which revision was suggested. CONCLUSIONS: We believe that the size of the defect is important for the reconstruction of cranial vault defects and that using a standard algorithm can increase the success rate.

Augmentation of craniofacial defects using alloplastic material.

BACKGROUND: Alloplastic materials are increasingly being used in augmentation of craniofacial defects because of its ready availability, good aesthetic outcome and absence of donor site morbidity. This paper highlights experience in the use of heat-cured acrylic in augmentation cranioplasty. SUBJECTS AND METHODS: The management of three patients with anterior skull defect who presented at the Dental and Maxillofacial Surgery Clinic of the Aminu Kano Teaching Hospital over a five-year period is presented. RESULTS: There was good aesthetic outcome in all the patients and no complications were recorded. CONCLUSION: Augmentation of craniofacial defects using customized prefabricated heat-cured acrylic provides patients with a durable, stable and structural repair of craniofacial defects with good aesthetic outcome.

Surgical treatment of metastatic tumors of the femur.

OBJECTIVE: To evaluate the patients functional outcome and pain control after resection of metastatic femoral tumors. MATERIAL AND METHODS: A prospective randomized clinical study was conducted, which included 26 cases of metastatic tumors of the femur with an associated pathologic fracture. These selected cases were randomly divided into two groups based upon the using of methylmethacrylate cement in fracture fixation. Group 1 (n=13) included all cases where the fractures were treated with bone cement augmentation. Group 2 (n=13) included all cases where the fractures were treated without bone cement augmentation. Functional outcome was evaluated according the American Musculoskeletal Tumor Society system. RESULTS: Good and excellent pain control was achieved in 61.5%, satisfactory in 38.5% of all cases in the Group 1 versus 15.5% (P=0.015) and 69% (chi(2)=2.4762; P=0.115) of all cases in the Group 2. Functional outcome after femoral metastasis resection and pathologic fracture fixation was significantly better in the Group 1. Total lower extremity function of full normal function was 67% in the Group 1 versus 49% in the Group 2 (P<0.05). We did not observe significant difference between patients' postoperative survival in the groups (P>0.05). The postoperative durability of stable pathologic fracture fixation was shorter in the Group 2 (273.9+/-51.7 vs. 358.9+/-116.8 days) comparing with Group 1 (P=0.03). CONCLUSIONS: The introduction of bone cement as the adjunct to the pathologic femoral fracture fixation significantly improved the clinical our study results: we achieved better functional outcome and better pain control.

[Surgical treatment of humeral metastatic tumors]. / Chirurginis zastikaulio metastaziniu naviku gydymas.

OBJECTIVE: To evaluate the functional outcome and pain control in patients after resection of humeral metastases. MATERIAL AND METHODS: A prospective randomized study of 24 cases of metastatic disease of the humerus with an associated pathologic fracture was carried out. The selected cases were divided into two groups based on the using methylmethacrylate cement for fracture fixation. Group 1 (n=12) included all cases in which the fracture was treated with bone cement augmentation. Group 2 (n=12) included all cases in which the fracture was treated without bone cement augmentation. Functional outcome was evaluated according to the American Musculoskeletal Tumor Society system. RESULTS: Good and excellent pain control was achieved in 95% of cases in both groups. Functional outcome after resection of humeral metastases and pathological fracture fixation was significantly better in Group 1. Total function in five patients (45%) accounted for 86% and in three patients (25%) for 83% of full normal upper extremity function, whereas in Group 2, total function in six patients (50%) accounted for 70% and in three patients (25%) for 83% of full normal upper extremity function. The rate of fixation failure was significantly greater in Group 2, where fixation instability was observed in 50% (n=6) of cases (P=0.03). There were no significant differences in complication rate (in 50% of cases, mechanical instability occurred after fixation with intramedullary nail and in 50% of cases after fixation with plates). CONCLUSIONS: The introduction of bone cement as an adjunct to fixation of pathologic fracture improved clinical results and reduced the rate of fixation failure.

[Vertebro-plasty: a rheumatologist's point of view]. / Les vertébroplasties: point de vue du rhumatologue.

Percutaneous vertebro-plasty is an efficient treatment of the symptomatic vertebral compression fracture refractory to optimal medical therapy. The procedure is used for neoplastic lesions, aggressive angioma, but also osteoporotic compression fractures. In order to adequately advice our patients, it is essential to know its indications and possible complications. However, to practice a vertebro-plasty for an osteoporotic compression fracture without any long term management of the osteoporotic disease is useless. Unfortunately, it still happens too often and it is essential that orthopedic surgeons, general practitioner, radiologist, rheumatologist, and any practitioners work together to guarantee the optimal management of our patients.

From computerized tomography data processing to rapid manufacturing of custom-made prostheses for cranioplasty. Case report.

Cranioplasty is a surgical repair of a structural or morphological deformity of the skull, involving the resection, remolding and displacement of the bones of the head. As it pertains to abnormal head shape, cranioplasty is an operative procedure aimed to fill a gap in the cranial theca or to replace bone removed either as a result of trauma or infection, by means of a biocompatible artificial bony substitute. In the present paper authors report a case of custom-made cranioplasty for the reconstruction of a large bilateral skull defect, based on advanced computerized tomography data processing and rapid prototyping (stereolithography) techniques.

Recurrent Osteoma Overlying a Methylmethacrylate Bone Cement Cranioplasty: A Rare Case.

Osteomas are generally benign tumors of the skull that affect all age groups and are diagnosed in the fourth or fifth decade of life, and are rare in childhood. Surgical resection is curative and malignant transformation is very rare. A 12-yearboy who had undergone a craniotomy for resection of a parietal osteoma four years ago, followed by a cranioplasty with methylmethacrylate bone cement, presented to our clinic with an expanding mass overlying the cranioplasty. Upon reoperation, the mass was totally excised, and the parietal cranial defect was repaired using methylmethacrylate bone cement. On histologic examination, the mass was found to be a recurrent osteoma overlying the methylmethacrylate bone cement. In this report, we discuss the etiologies of recurrence of osteoma and treatment options of these rare cases. We believe that this recurrence resulted from contamination of the surgical area and cranioplasty materials with osteoma material. Extensive washing of the cranioplasty materials and perioperative area may prevent recurrence of such tumors.

Fatal fat embolism after vertebroplasty: identification of the high-risk patient.

We report a rare complication of autopsy-proven fat and bone marrow embolization following percutaneous vertebroplasty in a patient who had no evidence of cement leakage. Cement injection was done during one patient encounter, covering 3 vertebral levels by using a unipedicular approach. Patients may have complications even without polymethylmethacrylate leakage.

Symptomatic refractures after vertebroplasty in patients with steroid-induced osteoporosis.

BACKGROUND AND PURPOSE: Refracture after percutaneous vertebroplasty in patients receiving oral glucocorticoid therapy has caused some patients and referring physicians to have negative perceptions concerning the efficacy of the initial vertebroplasty treatment. The purpose of this study was to analyze symptomatic refractures after vertebroplasty in patients on oral steroid therapy. We hypothesized that the higher refracture rate of patients on oral glucocorticoid therapy after percutaneous vertebroplasty is due not to an inadequacy of the procedure but rather to a naturally higher predisposition of these patients to refracture compared with patients with primary osteoporosis. METHODS: A retrospective analysis was performed on all osteoporosis patients having initial vertebroplasty from August 1999 to August 2003. The follow-up period was limited to 1 year after initial vertebroplasty session, with the last follow-up date ending in August 2004. Data were collected on 387 osteoporosis patients. RESULTS: Of the patients with primary osteoporosis, 20.6% patients refractured whereas 37.8% of the patients with steroid-induced osteoporosis had symptomatic refractures within 1 year of initial vertebroplasty. Relative risk of refracture within 1 year for the patients with steroid-induced osteoporosis was 1.84 compared with the patients with primary osteoporosis. In addition, the patients with steroid-induced osteoporosis were more likely to refracture after their second treatment session (within 1 year of initial vertebroplasty) than those with primary osteoporosis. CONCLUSION: Patients presenting on oral steroid therapy at their initial vertebroplasty are almost twice more likely to have symptomatic refractures than primary osteoporosis patients within 1 year of initial vertebroplasty.

[Copolymer of 2-hydroxyethyl methacrylate for cerebral arteriovenous malformation: an experimental study].

OBJECTIVE: To investigate the feasibility of using methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA) to embolize cerebral arteriovenous malformations (AVM). METHODS: Methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA) in the ratio of 9:1 were solved in 16% alcohol so as to make a kind of copolymer (CoHEMA). 12 g glass beads 2 mm in diameter were put into a container so as to construct an in vitro model of AVM. The container was connected with a normal saline bottle via microcatheter. CoHEMA, as embolized, was injected through the microcatheter and the diffusion of CoHEMA was observed till the water flow was stopped. CoHEMA was injected through microcatheter into the pharyngeal ascending arteries near the rete mirabile (RMB) tissue, similar to the human AVM, under digital subtraction angiography until satisfactory embolization was obtained, totally 9 RMB tissues in 7 pigs. Five pigs were injected with normal saline as controls. The pigs were killed 2 days, 2 weeks, and 6 months after embolization respectively and the bilateral RMB tissues were taken out to undergo pathological examination. RESULTS: Nine AVM models in vitro were constructed with the copolymer dispersed symmetrically among the glass beads and stopped the fluid across the model effectively. No copolymer adhered to the wall of microcatheter. Nine RMB tissues of 6 pigs were embolized by using CoHEMA. Six of the seven pigs survived the procedure except one died of too fast injection of copolymer in the primary stage. Follow-up angiography was performed in four pigs and found that no recanalization occurred and the copolymer was diffused in the vessels 80-150 microm in diameter. In the specimens obtained 2 days after embolization, neutrophilic granulocytes scattered surrounding the copolymer, suggesting minor inflammatory reaction. In the specimens obtained 2 weeks after embolization no vessel wall damage and morphological change were found except minor inflammatory reaction inside the vessels and surrounding tissues. In the specimens obtained 2 to 6 months after embolization hyperplasia of connective tissue, minor or mediate chronic inflammatory reaction, and giant cell reaction inside the vessels and surrounding tissues. CONCLUSION: With low viscosity, better biocompatibility, and embolic instability, and easy to be injected through delivery microcatheter, CoHEMA is an excellent non-adhesive embolic material and can be used in embolic treatment of cerebral AVM.

Pediatric thoracic lymphangiomatosis: is chest wall resection too radical?

Lymphangiomas account for 5% to 6% of all pediatric neoplasms. Complex pathologic processes often present a diagnostic and treatment challenge. Radical and major surgery might have a role in complex cases when medical treatment fails.